Boiler arrangement



Sept. 24, v1929.

H.- FECHT BOILER ARRANGEMENT Filed Dec. 8, 1925 INVENT-OR 1 1 1 I 1 1 I I I. r 1 1 1 1 1 1 1L 1 I I 1 I 11 1 1 1 1 1 1 j/ 1 P 1 u 1 1 1 1 1 1 1 1 1 1 1 1 1 A 1 1 .l /l 1 1 1 1 .1 1 1 1 1 1 I l 1 \A 1 1 1/ 1 1 I I 1 1 H 1 1 H 1 I 1! 1 1 1 1 1 I i 1 1 1 1 1 1 1 1 1 11/5 ATTORNEY.

Patented Sept. 24, 1929 UNITED STATES PATENT OFFICE HERMANN FECHT, OF BERLIN, GERMANY, ASSIGNOR TO KOHLENSOHEID'UNGS-JGE- SELLSCHAF'I M. B. H., OF BERLIN, GERMANY, A. CORPORATION OF GERMANY BoILEE ARRANGEMENT Application filed December 8, 1925, Serial No. 74,003, anil in Germany December 11, 1924.

g This invent-ion relates to a new boiler system with pulverized coal burning furnace.

In burning pulverized coal various requirements are to be respected whereby the principle structure of the boiler arrangement is more or less fixed. For instance the furnace must be of sufiicient extension, the flame must be so conducted, as to obtain complete combustion.

The ex erience has shown that no good results can e obtained if these requirements are not respected.

Nevertheless the efiiciency and economy of the combustion and of the boiler may be enlarged by simplifying the construction, by

reducing the loss of radiating heat etc. The invention relates to improvements in this regard The first object of the invention consists 'in 2o having the furnace arranged within the boiler structure, whereby the extension of the plant is reduced, hereby maintaining the possibility of introducing additional air into the combustion chamber and of controlling the combustion from the outside.

Another object of the invention is to reduce the radiation losses of heat by enveloping the parts of the boiler plant of high temperature by parts of relatively low temper- 30 ature.

For the sake of greater clearness I have hereinafter explained my invention in connection with an illustrative form of water tube boiler. It will be understood, that the ."3 invention'is not limited to this particular application and embodiment but can be otherwise carried out and applied.

In the drawing Fig. 1 is a vertical section through a boiler 1 having the combustion chamber arranged between the boiler elements the boiler and the furnace being enveloped by air preheaters and economizers respectively.

Fig. 2 is a cross section through the boiler taken at line AB of Fig. 1.

The boiler as shown in the drawing consists of four upper drums a and two lower drums b which are connected with each other by a plurality of tubes 0 and d which are arranged m a set of parallel rows. The tubes d are inclined thus covering the combustion space 6 1n upward direction. The combustlon chamber is enclosed by the two lower drums b and is provided at its lower part with three ash-pits over which two rows of tubes 9 are arranged crossing each other and formmg a water screen. These tubes are connected with headers h and i, the headers 2' have connection with the outside upper boiler drums respectively by means of tubes k which are lying between the tubes 0 while the headers h are connected with the lower boiler drums b by means of vertical tubes m which cover thefurnaces walls Z. In this way the water screen tubes are enclosed in the watercirculation of the boiler.

The pulverized coal is introduced into the furnace by means of the burners n, through which the fuel enters the combustion chamber in a downward direction: The burners are arranged at the opposite front sides of the boiler as indicated in dotted lines in Fig. 2.

. It will be understood, that the burners are arranged in such a way that they may easily be controlled.

After having lost its momentum the flame stream takes an upward direction and enters the boiler flues. On its way it is directed by suitably arranged bafiles. Then the gases pass through the economizers s on the side of the boiler above mentioned and in changing their downward direction they enter into the air-preheaters r opposite the side walls of the furnace. In this way the furnace and the centre part of the boiler-in other words-- the points of high temperature are kept as heat tight as possible and the sensible heat of the gases is used extensively.

Additional air is introduced through openings 0 in the walls 12 of the furnace. These openings may be kept closed against the outside by means of valves 9. The additional air is heated in the preheaters 1' as well as while flowing through hollow compartments of the furnace wall,

As shown in Fig. 2 of the drawing the furnace wall is hollow throughout its whole extension and the hollow compartments are connected with the air-preheaters thus fostering the preheating effect; but it will be understood that sometimes it is advantageous onl to have the front walls equipped with ho low compartments in respect to the fact that the side walls are effectively kept cool by the 5 vertical tubes m and therefore do not need supplementary cooling As shown in Fig. 1 of the drawing the walls enclosing the air-preheaters form in their lower extensions hopperlike channels t, in

which dust and ash particles are collected for being removed by means of screws or other suitable devices.

a While I prefer to use the constructionas illustrated in the drawings and as above described, it will be understood that I do not desire to limit myself to the use of the detailed forms of construction precisely as set forth inasmuch as it is evident that changes may well be made in the construction without departing from the spirit of my invention.

I claim:

In combination, a boiler, acombustion chamber therebeneath, additional boiler tubes defining side walls of said chamber, water 2 tubes extending across the bottom of said chamber, headers located outside said chamber into which said side and bottom tubes are connected, boiler flues extending along sides of said boiler and combustion chamber and 0 economizers in said flues, the flues being spaced from the combustion chamber so that access may be had to said headers.

In testimony whereof I aflix my signature.

5 HERMANN FEGHT. 3 

